For inspecting a printed substrate on which a plurality of electronic components is mounted, a complex inspection device is known. As disclosed in Japanese Patent Application Publication No. H2-52246 and Japanese Patent Application Publication No. 2004-340631, the device is configured to achieve both transmissive inspection using X rays and external inspection using visible light.
The complex inspection device is provided with an X-ray imaging apparatus for transmissive inspection and an optical imaging apparatus for external inspection.
Regarding the X-ray imaging apparatus, Japanese Patent Application Publication No. H2-52246, for example, discloses an X-ray source and an X-ray image sensor of which the relative opposition interval with respect to the X-ray source is adjustable. Regarding the optical imaging apparatus, Japanese Patent Application Publication No. H2-52246 also discloses a mirror which is integrally movable with the X-ray imaging apparatus, and a vidicon tube which is fixed to the X-ray imaging apparatus and captures images of an inspection object portion via a mirror.
Regarding another X-ray imaging apparatus, Japanese Patent Application Publication No. 2004-340631 discloses an X-ray source (X-ray irradiation unit) and an X-ray imaging unit (CCD camera) which oppose each other via an electronic component which is an inspection object. Regarding the optical imaging apparatus, Japanese Patent Application Publication No. 2004-340631 also discloses a mirror being arranged coaxially between the electronic component and the X-ray irradiation unit, and an imaging apparatus which captures images by receiving light, which is reflected by the mirror, from an electronic component. The X-ray irradiation unit of Japanese Patent Application Publication No. 2004-340631 is disposed fixedly. An object substrate or an inspection object on which electronic components are mounted is configured to be movable in a perpendicular plane with respect to the direction of X-ray radiation from the X-ray irradiation unit.
According to the devices in the aforementioned prior art, it is possible to dispose the mirror on the path of the X-rays traveling through the inspection object portion, and to carry out simultaneously transmissive inspection by X-rays and external inspection by an optical camera, so that there is an advantage of improving inspection efficiency.